Remote Restart is an high availability solution(but not alternative to PowerHA) of Power systems since Power 7. It means; restarting an lpar on a remote physical frame when local frame crashed. But because of "Remote Restart" has some difficulties(more steps and configurations), there is a new and simplier method which comes with Power 8; "Simplified Remote Restart - SRR"
This post is about conventional HMC cli method, it is not about environments that use PowerVC.
Here are the prerequisites for SRR;
-Power firmware 820 or later
-VIO server 22.214.171.124 or later
-HMC V8 R8.2.0 or later
-If Shared Storage Pool is used minimum HMC level is V8 R8.4.0 and VIOS level is 126.96.36.199
Check capabilities of power server at HMC, you should see "Simplified Remote Restart" as enabled. Here are the steps;
1. Disable ghostdev in OS. This will disable recreation of ODM when system changes. This step is same for PowerVC environments.
chdev -l sys0 -a ghostdev=0
2. To enable SRR on an lpar, you need to power off it. To enable run this command at HMC;
chsyscfg -r lpar -m physical_server_name -i "name=lpar_name,simplified_remote_restart_capable=1"
3. Check it. You should see this expressions at output; "simplified_remote_restart_capable=1,remote_restart_status=Remote Restartable". If everything is OK, power on it.
lssyscfg -m physical_server_name -r lpar --filter "lpar_names=lpar_name"
4. Map volumes of lpar to destination frame’s VIO servers and run “cfgmgr” on them. This can be done before physical server crash or during SRR. Actually if you can't do LPM to a physical server, you can't do SRR. This step also means, destination server's virtualization configuration(network, disk...etc) should fit with source one and lpar should be fully virtualized.
5. Validate SRR. This command should return nothing. If returns something, you should fix errors.
rrstartlpar -o validate -m source_physical_server -t destination_physical_server -p lpar_name
6. Do the SRR. Actually if you want to test it you should power off physical server that lpar is running on.
rrstartlpar -o restart -m source_physical_server -t destination_physical_server -p lpar_name